docs: def scan_setup_py():
      """Validate the contents of setup.py against Versioneer's expectations."""
      found = set()
      setters = False
      errors = 0
      with open("setup.py", "r") as f:
          for line in f.readlines():
              if "import versioneer" in line:
                  found.add("import")
              if "versioneer.get_cmdclass(" in line:
                  found.add("cmdclass")
              if "versioneer.get_version()" in line:
                  found.add("get_version")
              if "versioneer.VCS" in line:
                  setters = True
              if "versioneer.versionfile_source" in line:
                  setters = True
      if len(found) != 3:
          print("")
          print("Your setup.py appears to be missing some important items")
          print("(but I might be wrong). Please make sure it has something")
          print("roughly like the following:")
          print("")
          print(" import versioneer")
          print(" setup( version=versioneer.get_version(),")
          print("        cmdclass=versioneer.get_cmdclass(),  ...)")
          print("")
          errors += 1
      if setters:
          print("You should remove lines like 'versioneer.VCS = ' and")
          print("'versioneer.versionfile_source = ' . This configuration")
          print("now lives in setup.cfg, and should be removed from setup.py")
          print("")
          errors += 1
      return errors